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Interplay between interference and Coulomb interaction in the ferromagnetic Anderson model with applied magnetic field

Pedersen, Jonas LU ; Bohr, Dan; Wacker, Andreas LU ; Novotny, Tomas; Schmitteckert, Peter and Flensberg, Karsten (2009) In Physical Review B 79.
Abstract
We study the competition between interference due to multiple single-particle paths and Coulomb interaction in a simple model of an Anderson-type impurity with local-magnetic-field-induced level splitting coupled to ferromagnetic leads. The model along with its potential experimental relevance in the field of spintronics serves as a nontrivial benchmark system where various quantum-transport approaches can be tested and compared. We present results for the linear conductance obtained by a spin-dependent implementation of the density-matrix renormalization-group scheme which are compared with a mean-field solution as well as a seemingly more advanced Hubbard-I approximation. We explain why mean field yields nearly perfect results while the... (More)
We study the competition between interference due to multiple single-particle paths and Coulomb interaction in a simple model of an Anderson-type impurity with local-magnetic-field-induced level splitting coupled to ferromagnetic leads. The model along with its potential experimental relevance in the field of spintronics serves as a nontrivial benchmark system where various quantum-transport approaches can be tested and compared. We present results for the linear conductance obtained by a spin-dependent implementation of the density-matrix renormalization-group scheme which are compared with a mean-field solution as well as a seemingly more advanced Hubbard-I approximation. We explain why mean field yields nearly perfect results while the more sophisticated Hubbard-I approach fails even at a purely conceptual level since it breaks hermiticity of the related density matrix. Furthermore, we study finite bias transport through the impurity by the mean-field approach and recently developed higher-order density-matrix equations. We found that the mean-field solution fails to describe the plausible results of the higher-order density-matrix approach both quantitatively and qualitatively, as it does not capture some essential features of the current-voltage characteristics such as negative differential conductance. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Physical Review B
volume
79
publisher
American Physical Society
external identifiers
  • wos:000264769300084
  • scopus:63149113416
ISSN
1550-235X
DOI
10.1103/PhysRevB.79.125403
language
English
LU publication?
yes
id
96bf003d-9fd0-45f5-bd03-9904b8963fe5 (old id 1268473)
date added to LUP
2008-11-19 10:08:16
date last changed
2017-01-01 07:59:51
@article{96bf003d-9fd0-45f5-bd03-9904b8963fe5,
  abstract     = {We study the competition between interference due to multiple single-particle paths and Coulomb interaction in a simple model of an Anderson-type impurity with local-magnetic-field-induced level splitting coupled to ferromagnetic leads. The model along with its potential experimental relevance in the field of spintronics serves as a nontrivial benchmark system where various quantum-transport approaches can be tested and compared. We present results for the linear conductance obtained by a spin-dependent implementation of the density-matrix renormalization-group scheme which are compared with a mean-field solution as well as a seemingly more advanced Hubbard-I approximation. We explain why mean field yields nearly perfect results while the more sophisticated Hubbard-I approach fails even at a purely conceptual level since it breaks hermiticity of the related density matrix. Furthermore, we study finite bias transport through the impurity by the mean-field approach and recently developed higher-order density-matrix equations. We found that the mean-field solution fails to describe the plausible results of the higher-order density-matrix approach both quantitatively and qualitatively, as it does not capture some essential features of the current-voltage characteristics such as negative differential conductance.},
  articleno    = {125403},
  author       = {Pedersen, Jonas and Bohr, Dan and Wacker, Andreas and Novotny, Tomas and Schmitteckert, Peter and Flensberg, Karsten},
  issn         = {1550-235X},
  language     = {eng},
  publisher    = {American Physical Society},
  series       = {Physical Review B},
  title        = {Interplay between interference and Coulomb interaction in the ferromagnetic Anderson model with applied magnetic field},
  url          = {http://dx.doi.org/10.1103/PhysRevB.79.125403},
  volume       = {79},
  year         = {2009},
}